Since a=rac{1}{n} where $n$ is a positive integer with $n>1$, then $0<a<1$ and rac{1}{a}=n>1. Thus, 0<a<1<rac{1}{a}, which eliminates choices (D) and (E). Since $0<a<1$, then $a^{2}$ is positive and $a^{2}<a$, which eliminates choices (A) and (C). Thus, 0<a^{2}<a<1<rac{1}{a}, which tells us that (B) must be correct.